Furnace



Feb 12,1929.,

H. E. CANNON ET AL FURNACE Filed Feb. 28, 1921 Patented Feb. l2, 1929.

UNITED STATES 1,701,836 PATENT oFFICE.

HIBAM '.B. CANN ON, OF SARNIA, ONTARIO, CANADA, AND JOHN W. CANNON, OF BOSTON, MASSACHUSETTS, ASSIGNORS T THE CABBOBUNDUM COMPANY, OF NIAGARA. FALLS, NEW YORK, A CORPORATION OF PENNSYLVANIA.

IUBNACE.

application 1aed February as, 1921. serial m4413339.

This invention relates to steam-boiler furnaces, and more particularly to furnaces of the locomotive type, and has for 1ts general object to effect-the efficient and economical' heating of the boilers for such furnaces; also to enable such heating to be accomplished in and throu h the use of pulverized fuel.

In the drawings forming a art hereof Fig. 1 represents the central longitudinal sectional elevation of the rear end of a locomotive boiler, showing our invention ap lied thereto; Fi 2 a sectional elevation o the rear of suc boiler, the said section being taken between the slabs 10 and the front ends of the partitions 12.

Describingthepartsby reference characters,

1 denotes the outer shell and 2 the cylindric' inner or fire box shell of a locomotive, the re box shell projecting into the main body of the boiler from the rear or firing' end thereof, as is customary with locomotive boiler construction. 'At the front of the tire box is a tube sheet 3 from which the fire .tubes 4 extend forwardly, as is the usual practice.

Mounted in the fire box and extending forward from the rear thereof are a plurality of combustion chambers, each indicated generall at 5. Three such combustion chambers are s. own, although the number may be varied as desired. Each chamber is composed of a plurality of sections each made up of a top slab 6, a bottom slab 7 and side slabs 8,

the sections bein united by joints 9, to which, if desired, a reractory cement preferably of the same material as that employed for the slabs,-carborundum. The rear section of each chamber is provided with a closure slab 10 and the front section is formed from a curved slab 11 having concave face presented inwardly.

Between the top and the bottom of each combustion chamber there is a partition 12 which projects forward from the slab 10 toward the front wall 11 of said chamber, be-

i ing spaced at its front endfrom such wall.

The front section of each chamber is provided with an outlet pipe 13, preferably of.

the same material as the Nsaid section, which outlet pipe projects through an aperture 14 in the bottom ofthe boiler and is ada ted t0 discharge into an ash pit 15 having oors 16 by which it and the combustion chamber are sealed against the admission of'air.

Each combustion chamber is so mounted is applied,

-as' to slope downwardly from the rear to the front thereof, whereby the bottom wall will have an inclination of about 15 to the horizontal. The slabs and the partition of which each cumbustion chamber are composed consist of carborundum, preferably mixed with a small portion of binding or bonding material (such as tire clay) and molded to shape. A

combustion chamber made of this material is practically indestructible by high temperatures, has a low coelicient of expansion, whereby it will not crack on rapidly heating and. cooling, is extremely permeable to heat, and possesses great heat radiating capacity.

' Each of the combustion chambers is supported on the inner bottom sheet of the fire box, preferably by means of aslab of carborundum indicated at 17 and generally made up of a number of sections, the said slab havmg projections 17 at its upper surface adapted to en age the bottom Walls ofthe combustion cham rs and providing, betweensuch projections, spaces for the circulationl of air. The front end of each combustion chamber is supported against the action of gravity by means of suitably shaped blocks 18"'and'19, preferably of carborundum, interposed between such end and the bottom sheet-of the fire box and between suchend and the'tube sheet 3. Between the top of each combustion chamber and the top of the fire boxare blocks 20. Extending through the plate or slab 10 and below the partition 12 is a burner 21 through which a mixture of pulverized fuel (such as coal) and air is injected. This mixture, being ignited, traverses the combustion `spaces formed beneath and abovethe partit1on, the products escaping throu h the slots 6 provided between the s abs 6. hese slots are arranged so as ,to provide outlet ports which progressively increase in area from the front toward the rear of ythe combustion chamberifor the purpose of equalizing the delivery of the products of combustion through the said openings or slots.

As is well known, in the combustion of nely ,divided fuel, such as coal, a certain proportion of y sla This material Aten s to accumulate upon the relatively'cold surfaces of boilers, constituting a serious detriment to the eiicient heating of the latter and making 1t necessary to shut down such boilers repeatedly for the purpose of removing this material. Because or clinker is produced. Y

of the temperature to which, the combustion chambers are heated by the fuel, the clinker or slag is maintained 1n a molten condition, and the inclination of thepartition and lthe bottom of each chamber causes the slag or clinker to be discharged by gravity thru the outlet 13. Furthermore, the shape of the front wall of each combustion chamber, in

cooperation with the adjacent end of the partition, tends to throw outwardly and against such wall any ash that may be in the burning mixture, which ash will also be d1;

from the outlet 13.

By locating the openings or slots 6a as shown, the products of combustion are'directed against the upper or crown sheet of the fire box and thence pass forwardly through the fire tubes 4. .i I

In operation, each of the combustion chambers shortly becomes heated to a temperature at which its exterior assumes a yel-` lowish white color, resulting, not only in the most yeiiicient combustion of the fuel, butin the very effective heating by radiation andvconvection of the surrounding Wall of the lire box. By the time the products shall have reached the openings 6, all of the solid carbon will have been consumed, with thev re sult that there will be no deposition of cartime and wit bon upon the wall of the fire box or within the tubes.

The two side combustionlchambers of the combustion-chamber assembl are provided with curved lateral walls which are substantially concentric with the lwall 2 of the: fire box and are in close proximity to such wall. This arrangement, together with the arrangement of the tops 5 and the openings therein, results in an extremely eicient heating b` radiation and convection ofthe re box wall vas Well as providing for additional heating kchamber a delivery connection, me'ansfor sealing said connection against the admission of air, the said chamber having a partition between the top and the bottom thereof and extending forwardly from the rear toward and s aced from the front wall, and being provi ed with a pluralitv of outlet openings 1n the top thereo the cross sectional area of such openings var ing pro ressively from the front toward t e rear o such top, and

means for supplying a mixture of yair and tral combustion chamber, each' of the lateral. l

combustion chambers having a curved lateral wall spaced' a short distance from the adjacent curved Wall of the fire box and each combustio'n chamber having an vupper wall adjacent to the Wall of the fire box thereabove and each chamber being closed at the front thereof, each combustion chamber having an outlet' near the rear thereof, and means for supplying a mixture of air and fuel to the rear of each combustion chamber, each combustion chamber being composed of refractory material of high heat permeability.

3. The combination, with a locomotive boiler and a substantially cylindric fire box, of a central combustion chamber and lateral combustion chambers spaced from the'` centra-l combustion chamber, each of the lateral combustion'chambers having a curved lateral Wall spaced a short distance from the curved wall of the fire box and each combustion chamber being closed at its front end and having an upper Wall adjacent to the wall of the fire box thereabove, each combustion chamber being provided with a partition intermediate fthe top and bottom thereof and extending from the rear toward and spaced from the frontthereof, each combustion chamber having an outlet near'the rear thereof, and means for 'supplying a mixture of air and fuel to the rear of each combustion chamber .below the partition therein, each combustion chamber being composed of .refractory material of high heat permeability.

4. The combination, with a locomotive boiler and fire box, of one or more combustion chambers mounted in said fire box and extending forward from the rear thereof, each such combustion chamber being closed at its frontend and vhaving a partition intermediate the top and bottom thereof and projecting forwardly from the rear toward and spaced from the front of such chamber, the upper wall of each combustion chamber being contiguous to but spaced from the fire-box wall thereabove and provided with a plu,-

rality of outlet openings varying progres sively in cross sectional area from the front toward the rear of such top, and means forl supplying a mixture of air and fuel to the rear of such chamber beneath the said partition, the said chamber being composed of krefractory material of highheat permeability.

5. The combination, with a locomotive boiler having a fire box, of a plurality of combustion chambers mounted in said fire box and extending forwardly from the rear morose cud thereof, each such combustion chamber having its top contiguous to but spaced from the wall of the fire box thereabove and provided with an outlet near the rear thereof, and braces interposed between the top and the front of each combustion chamber and the corresponding parts of the fire box, the said combustion chambers and braces being composed of refractory material ofhigh heat permeability.

6. rlhe combination, with a locomotive boiler having a fire box, of a plurality of spaced combustion chambers mounted in said fire box. the said combustion chambers having walis in proximity and conforming in contour to the corresponding portions of the fire box, each combustion chamber having an outlet near the rear thereof, means for supplying a mixture of air and fuel to each of said combustion chambers, the products of combustion'being delivered through the outlets thereof in operative relation to the wall of the fire box thereabove, and braces interposed between the said combustion chambers and the fire box, said combustion chambers and braces bein composed of` refractory material of high eat permeability.

7. IThe combination, with a locomotive boiler having a re box, of a combustion chamber mounted in said fire box and extending forward ifrom the rear thereof, said combustion chamber being inclined downwardly from the rear toward the front thereof, said chamber bein closed at its frontend and having a partition extendin from the rear toward but spaced from suc front end, the said partition being arranged intermediate the top andpbottom of said chamber, the said chamber having an outlet y, opening near the rear thereof, means for supplying a combustible mixture to the said chamber on the opposite side of the said partition from the said opening, a support for the bottom of said combustion chamber extending forwardly from the rear of saidfire box, the chamberengaging surface of said support being inclined downwardly from rear to front there of, and means inte osed between the combustion chamber an the fire box for bracing the said chamber, the said combustion chamber, partition, support and bracing means being composed principally of carborundum..

8. The combination, with a locomotive boiler having a lire box, of a lurality of laterally spaced combustion cham ers mounted in said fire box and extending forwardly from the rear end thereof, each combustiom chamber having a top, bottomand front Wall of refractory material of high heat permeability, the said top, bottom and front walls being arranged ad]acent to the top, bottom and front of the lire box, respective whereby each combustion chamber is a apted to heat such top, bottom and front of said fire box by radiation, and means for circulating and burning a combustible mixture within each such combustion chamber.

9. The combination, with a. locomotive i boiler having a fire box, of a plurality of laterally spaced combustion chambers mounted in said fire box and extending forwardly from the rear end thereof, each combustion chamber having a top, bottom and front wall in proximity to the top, bottom'A and front of the fire box, respectively, and the combustion chambers at each end of such lateral series of chambers having each aside wall in proximity to the corresponding side portion of the said fire box, one wall of each of the combustion chambers bein providedl with one or more outlets for pro ucts of combustion, and means for supplying a combustible mixture to each of said combustion chambers.

10. The combination, with a locomotive boiler having a fire box, of a combustion chamber mounted in said fire box and extending forwardly from the rear end thereof, the said combustion chamber having a top, bottom and front wall of refractory material having high heat permeability, the said top, bottom and front walls being m proximit to the top, bottom and front of the lire ox, respectively, whereby the said combustion chamber is adapted to heat the top, bottom and front ofrthe fire box by radiation, one of the walls of the combustion chamber being provided with one or more openings for the dischar e of products of combustion, and means or su plying combustible mixture to the said combustion chamber.

In testimony whereof, we hereunto ax our signatures.

JGHN W. CANNON. HIRAM B. CANNON. 

